Sleep: Part 2 –
Your health & performance depends upon it

March 2009 – Vol. 13, No. 3

Editors: Janet M. Pollard, MPH; and Carol A. Rice, Ph.D., R.N.

“Before Thomas Edison’s invention of the light bulb, people slept an average of 10 hours a night; today, Americans average 6.9 hours of sleep on weeknights and 7.5 hours per night on weekends.”¹

“Approximately 70 million people in the United States are affected by a sleep problem. About 40 million Americans suffer from a chronic sleep disorder, and an additional 20–30 million are affected by intermittent sleep-related problems. However, an overwhelming majority of sleep disorders remain undiagnosed and untreated.”¹

“A majority of American adults (63 percent) do not get the recommended eight hours of sleep needed for good health, safety, and optimum performance. In fact, nearly one-third (31 percent) report sleeping less than seven hours each week night, though many adults say they try to sleep more on weekends.”¹

“…As many as 47 million adults may be putting themselves at risk for injury, health, and behavior problems because they aren’t meeting their minimum sleep need in order to be fully alert the next day.”¹

How Much Is Enough? Quantity & Quality

We know that insufficient sleep is directly linked to poor health (see Sleep: Part 1 [PDF]), but how do we know if we’re getting enough sleep to meet our health and performance needs? “Getting enough sleep refers to the amount of sleep you need to not feel sleepy the next day. If sleepiness interferes with or makes it difficult to do your daily activities, you probably need more sleep. Although sleep experts generally recommend an average of 7–9 hours per night, some people can get along with less while others need as much as 10 hours to feel alert the next day.

Sleep requirements vary over the life cycle. Newborns and infants need a lot of sleep and have several periods of sleep throughout a 24-hour time period. Naps are important to them as well as to toddlers, who may nap up to the age of 5. As children enter adolescence, their sleep patterns shift to a later sleep-wake cycle, but they still need around 9 hours of sleep.”² “Throughout adulthood, even as we get older, we need 7–9 hours of sleep. Sleep patterns may change, but the need for sleep remains the same”² (see States & Stages of Sleep, diagram 1 [PDF]). As older adults, we may experience shorter periods of deep sleep, finding ourselves sleeping more lightly and awakening more often during the night, but our need for that 7–9 hours of sleep does not change.³ (See What Happens as We Sleep [PDF].)

Be aware that quality of sleep is just as important as quantity. People whose sleep is frequently interrupted or cut short are not getting quality sleep. If you feel drowsy during the day – even during boring or monotonous activities – you are not getting enough sleep.^3,4 Other signs are a tendency to be unreasonably irritable with friends, family, or co-workers, and having difficulty concentrating or remembering facts.⁴ It is important to plan for sleep just as you would plan for a meeting. If you don’t schedule time to sleep, the consequences can be detrimental to both mind and body. “Planning your day so that you allow enough time to sleep is essential to your overall well-being and quality of life. Such planning includes allowing enough time to awaken – [ideally] without an alarm clock – so you get as much sleep as you need.”² “If you experience frequent daytime sleepiness, even after increasing the amount of quality sleep you get, talk to your doctor. He or she may be able to identify the cause of sleep problems and offer advice on how to get a better night’s sleep.”³

Common sleep problems include:

Why Nighttime Sleep? Our biological clock

Sleep is regulated in two ways.

The first process is the restorative process, which occurs naturally in response to how long you are awake – the longer you’re awake – the stronger is the drive to sleep.²
The second process controls the timing of sleep and wakefulness during the day-night cycle.² This process is controlled by your “internal biological clock – a tiny bundle of cells in your brain that responds to light signals through your eyes and promotes wakefulness. Because of the timing of the biological clock and other bodily processes, you naturally feel drowsy between midnight and 7 a.m. and again in the afternoon between 1 p.m. and 4 p.m.”⁵ (see States & Stages of Sleep, diagram 2 [PDF]). “This internal clock, which gradually becomes established during the first months of life, controls the daily ups and downs of biological patterns, including body temperature, blood pressure, and the release of hormones.”⁶

Night shift. The internal biological clock is one reason why night-shift workers often find themselves drowsy at work or having trouble falling asleep or staying asleep during the day, when their schedules require them to sleep. “Being sleepy puts them at risk for injuries on the road and at work. Night-shift workers are also more likely to have conditions such as heart disease, digestive disorders, and infertility, as well as emotional problems. All of these problems may be related, at least in part, to their chronic lack of sleep.”⁵

Jet lag. The internal biological clock also contributes to what we call “jet lag.” When traveling across time zones, it can be hard to adapt to new sleep and wake patterns. What results is that feeling of jet lag where we feel sleepy in the daytime, have trouble falling asleep or staying asleep at night, develop poor concentration, and irritability.⁵ “The good news is that by using appropriately timed cues, most people can change their biological clock, but only by 1–2 hours per day at best. Therefore, it can take several days to adjust to a new time zone (PDF) or different work schedule. Establishing a regular pattern of sleep with regular bed and wake times helps promote sleep by getting you in sync with your biological clock so you experience all of the sleep stages² (States & Stages of Sleep, diagram 3 [PDF]) and wake up feeling rested.

When We Don’t Sleep…Sleep debt

“The amount of sleep a person needs…increases if he or she has been deprived of sleep in previous days. Getting too little sleep creates a ‘sleep debt,’ which is much like being overdrawn at a bank. Eventually, your body will demand that the debt be repaid. We don’t seem to adapt to getting less sleep than we need; while we may get used to a sleep-depriving schedule, our judgment, reaction time, and other functions are still impaired.”⁷ In fact, many studies make it clear that being sleep deprived is dangerous.“Sleep-deprived people who are tested by using a driving simulator or by performing a hand-eye coordination task perform as badly as or worse than those who are intoxicated.”⁷ “As sleep debt mounts, the health consequences increase, putting us at growing risk for weight gain, diabetes, heart disease, stroke, and memory loss”;⁸ and “driver fatigue is responsible for an estimated 100,000 motor vehicle accidents and 1500 deaths each year.”⁷

“Fortunately, sleep doesn’t charge interest on the unpaid balance or even demand a one-for-one repayment. It may take some time, but you can repay even a chronic, long-standing sleep debt.”⁸ Some research suggests that the accumulated sleep debt can be worked down or ‘paid off.’”⁹ In the July 2007 issue of Harvard Women’s Health Watch, Dr. Lawrence J. Epstein, regional medical director of the Harvard-affiliated Sleep Health Centers, offers the following advice:

“Settle short-term debt. If you missed 10 hours of sleep over the course of a week, add three to four extra sleep hours on the weekend and an extra hour or two per night the following week until you have repaid the debt fully.
Address a long-term debt. If you’ve shorted yourself on sleep for decades, you won’t be required to put in a Rip Van Winkle-like effort to repay the hours of missed slumber. Nonetheless, it could take a few weeks to recoup your losses. Plan a vacation with a light schedule and few obligations – not a whirlwind tour of the museums of Europe or a daughter’s wedding. Then, turn off the alarm clock and just sleep every night until you awake naturally. At the beginning, you may be sleeping 12 hours or more a night; by the end, you’ll be getting about the amount you regularly need to awake refreshed.
Avoid backsliding into a new debt cycle. Once you’ve determined how much sleep you really need, factor it into your daily schedule. Try to go to bed and get up at the same time every day – at the very least, on weekdays. If need be, use weekends to make up for lost sleep.”⁸

How to Get Quality Sleep: Tips to a good night’s sleep

Let’s face it, sometimes getting enough good, quality sleep can be difficult. A baby awakens you; your spouse is snoring; you’re caring for others in your home; it’s hot and humid; the stress at work is keeping your mind running in circles, etc. Whatever the reason, sometimes sleep can be hard to come by. The following tips may help you make gains in the area of more quality and quantity sleep:

Stick to a sleep schedule. Go to bed and wake up at the same time each day – even on the weekends, if possible.⁵ This schedule helps set your biological clock and makes it easier to wake up on Monday mornings.⁷
Use your bed for sleep and intimacy. Don’t use your bed for anything but sleep and intimacy. Your bed should be associated with relaxation and sleep.^4,10
Exercise, but not too late in the day. Try to exercise 30 minutes a day. Daily exercise often helps people sleep. Avoid exercising closer than 5 or 6 hours before bedtime, however, since exercise close to bedtime can stimulate and increase alertness.^4,5,7,10
Avoid caffeine and nicotine. Both caffeine and nicotine stimulate the central nervous system.¹⁰ The stimulating effects of caffeine in coffee, colas, teas, and chocolate can take as long as 8 hours to wear off fully. Tobacco users also experience nicotine withdrawal during sleep, and some have more nightmares than non-nicotine users, which disrupts sleep. Giving up tobacco may cause more sleep problems at first, but the long-term effect on sleep and health is much better.¹¹
Avoid alcoholic drinks before bed. A “nightcap” might help you get to sleep, but alcohol keeps you in the lighter stages of sleep. You also tend to wake up in the middle of the night when the sedating effects have worn off.⁵
Avoid large meals and beverages late at night. A large meal can cause indigestion that interferes with sleep. Drinking too many fluids at night can cause you to awaken frequently to urinate.⁵ Try to finish eating all meals 2–3 hours before your regular bedtime.¹²
Drink a glass of fat-free milk before bed. The amino acid tryptophan in the milk will help make you feel sleepy.¹⁰ In fact, all dairy foods are a good source of tryptophan. Tryptophan converts to melatonin and serotonin in the body – both of which are thought to induce sleep. Other tryptophan-containing foods include oats, bananas, poultry, and peanuts.¹³ See Bedtime Snack Ideas (PDF) for more information.
Avoid medicines that delay or disrupt your sleep, if possible. Some commonly prescribed heart, blood pressure, or asthma medications, as well as some over-the-counter and herbal remedies for coughs, colds, or allergies can disrupt sleep patterns.⁵ Consult your doctor.
Nap, only if necessary. Night owls and shift workers are at the greatest risk for sleep debt. Napping an hour or two at the peak of sleepiness in the afternoon can help these individuals to supplement hours missed at night.⁸ Try not to take naps after 3 p.m. Though naps can boost your brain power, late afternoon naps can make it harder to fall asleep at night. Also, try to keep naps to under an hour.⁵ Ideally, naps should last 20–30 minutes for someone who is not working a night shift and needs some short-term alertness in the day.¹⁶ Those who take advantage of a 20-minute power nap during the work day report that they can then go back to work with renewed enthusiasm and energy.¹⁷
Relax before bed. Take time to unwind. A relaxing activity, such as reading or listening to music, can be a helpful part of your bedtime ritual.⁵ Avoid watching a TV show or reading a book that is stimulating, frightening, or violent right before bed.¹⁰
Take a hot bath before bed. The drop in body temperature after the bath may help you feel sleepy, and the bath can help relax you.⁵
Have a good sleeping environment. Make your bedroom cool, dark, quiet, and comfortable.¹⁸ Get rid of anything that might distract you from sleep, such as noises (PDF), bright lights (PDF), an uncomfortable bed, or a TV or computer in the bedroom. Keep the bedroom dark and the temperature on the cool side to help you sleep better.^4,5 If the room stays excessively humid, you may want to try a dehumidifier. If it is excessively dry (PDF), consider a humidifier.¹¹
Have the right sunlight exposure. Daylight is key to regulating daily sleep patterns. Try to get outside in natural sunlight for at least 30 minutes each day.⁵
Don’t lie in bed awake. Don’t get in bed before you are tired. If you find yourself still awake after staying in bed for more than 20 minutes, get up and do some relaxing activity until you feel sleepy. Then go back to bed. The anxiety of not being able to sleep (PDF) can make it harder to fall asleep.⁵
See a doctor if you continue to have trouble sleeping. If you consistently find yourself feeling tired or not well rested during the day despite spending enough time in bed at night, you may have a sleep disorder. Your family doctor or a sleep specialist should be able to help you.⁵

Sleep Medications: Talk with your doctor

Sleeping pills should only be used as a last resort¹⁸ – even over-the-counter sleep medicines. “Natural sleep is best. It’s physically restorative, and it usually provides enough dreaming time (REM sleep) to improve learning, memory, and mood.”¹⁹ Some people are turning to various dietary supplements (PDF) (particularly, melatonin [PDF] and valerian [PDF]), but little is known about their safety or effectiveness.²⁰ Sleep medications can have negative side effects and can interact with other medications or with existing medical conditions. So, it is very important to check with your doctor before taking any sleep medications.¹⁸ Your doctor can help you decide if a sleep medication or other apparatus (PDF) is right for you, as well as the type and appropriate dosage.²⁰

Most sleep experts agree that there are times when sleeping pills may be of help, such as during periods of pain or grief, or when sleep loss affects job performance.¹⁹ Sleeping pills, however, are a “temporary aid and shouldn’t be taken for more than a few days to a few weeks…. When taken for long periods or in higher than normal doses, sleeping pills can cause serious problems that far outweigh their benefits. Among other side effects, sleeping pills can:

mask the real causes of poor sleep, such as depression, heart trouble, asthma, and Parkinson’s disease, and delay treatment of these disorders;
interact with other medications or alcohol, often with serious, even deadly, results;
cause next-day grogginess or rebound insomnia – an inability to sleep that’s worse than the original problem; or
lead to high blood pressure, dizziness, weakness, nausea, confusion, short-term amnesia, and bizarre behavior that goes far beyond traditional sleepwalking to include ‘sleep binge eating,’ ‘sleep shoplifting,’ and ‘sleep driving’ – none of which the person remembers.”¹⁹ (See the FDA’s Side Effects of Sleep Drugs for more information.) See more information about sleep aids and talking with your doctor here (PDF).

Our Need for Sleep: Improving quantity & quality

There is a lot we can do to improve our quantity and quality of sleep, but we have to commit to doing it. In our 24/7 society, where we can choose to do business or have entertainment all day and night – it can be hard to slow down long enough to get some sleep. Remember, however, that the compromises we make in sleep are also compromises that may lead to poor performance and negative health consequences – for ourselves and often for others, too, where safety issues are concerned. Take time to schedule sleep. Use the suggested tips for better quantity and quality of sleep that seem right for you. If you still can’t seem to get enough sleep, consult your doctor. You may have a sleep disorder or underlying medical condition (PDF) that can be treated and allow you a good night’s sleep.

This document is meant for educational purposes only and is not intended to replace the advice of your doctor or other health care provider.

References:

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Sleep: Part 2 – Your health & performance depends upon it